1. Field of the Invention
This invention relates to an image forming apparatus having at least two features of photocopying and facsimile and it also relates to an automatic document feeder to be fitted to such an image forming apparatus.
2. Description of the Related Art
A known image forming apparatus disclosed in U.S. Pat. No. 5,177,546 includes a first document tray and a second document tray along with two feeding paths for the trays which can be switched for use so that the two sets of paper sheets of the documents are not be mixed up. It is, however, an apparatus dedicated to photocopying and the apparatus cannot facsimile. With the apparatus, a set of paper sheets of a document are normally put in each document tray with the last and first pages of the document placed at the bottom and the top thereof such that the sheets are fed to a scanner one by one, the sheet for the last page being fed first, and each sheet is turned up side down to have the right side face and scanned by the scanner located therebelow for photocopying. After the photocopying operation is over, the sheet is ejected out of the apparatus.
If the apparatus is additionally provided with the feature of facsimile, then the following problem will arise. As described above, for photocopying a set of paper sheets, or a document, the sheets are normally placed on a tray with the right side, in other words the desired side to be copied, facing upward and the last page located at the bottom and fed to the scanner one by one starting from the sheet for the last page. The photocopied sheets are then put in a receiving tray one on top of the other so that the original sequence may be maintained. On the other hand, when a set of paper sheets of a document are facsimiled by a facsimile apparatus, the first and the last pages of the document are respectively placed at the bottom and the top, respectively with the right side facing downward. Therefore, when a user who is accustomed to an ordinary facsimile apparatus uses such a dual-feature apparatus to facsimile a document, he or she may fail to place the first page at the bottom of the document, having all the pages face downward, to facsimile the entire document correctly.
The entire document can be facsimiled with such an apparatus only by placing the first page at the bottom and having all the pages face upward. However, all the sheets of the document have to be rearranged to place the first and the last pages at the bottom and the top of the document, respectively and have all the pages face upward. Such a rearranging operation is cumbersome and painstaking.